The present invention relates to a method for attaching a terminal contact set to a coaxial cable at its cable end and, in particular, to such a method using a contact frame having the terminal contact set integrally formed from a metal plate.
Generally, a coaxial cable is used as a transmission line and comprises a first conductor, as an center or inner conductor, centered inside, a first conductor, as an outer conductor, extending coaxial with the center conductor, a first insulator cover covering and insulating the center conductor from the outer conductor, and a second cover or an outer jacket covering and insulating the outer conductor.
When the coaxial cable is used for electrically connecting between a two electrical apparatus, cable ends thereof are processed to expose the center and outer conductor ends which are, in turn, connected to electrical circuits in the apparatus.
In order to make it easy to connect the center conductor and the outer conductor to the circuit, a terminal contact set are attached to the cable end. The terminal contact set is often assembled in a connector insulating as connector contacts to form an electrical connector such as a plug connector.
A set of the terminal contacts comprises a first contact element or a center contact to be connected to the center conductor end of the coaxial cable, and a second contact element or an outer contact to be the outer conductor of the coaxial cable.
In the prior art, the center contact and the outer contact are produced independently from each other by, for example, punching metallic plates to form center contact flat parts by use of a die and to form outer contact flat parts by use of a different die, respectively.
Subsequently, the outer contact is fitted to the outer conductor end and then mechanically fixed to the outer jacket, by deforming the outer contact flat plate. On the other hand, the center contact is fitted to the center conductor end and then mechanically fixed to the second cover, by deforming the center contact flat part.
However, the terminal contact set for the coaxial cable as described above is disadvantageous in that the center contact and the outer contact are independently produced into the flat parts by the use of the two different metallic plates and the two different dies.
In the meanwhile, attachment of the center contact and the outer contact to center conductor end and the outer conductor end of the coaxial cable is carried out in the manner wherein an increased number of steps are required and a work efficiency is extremely low so that an assembling operation inevitably requires a relatively long time. In the manner, at first, the center contact part is brought into contact with the center conductor and is deformed or crimped to press-fit to the center conductor. Thereafter, the outer contact part is brought into the outer conductor and deformed and crimped to press-fit to the outer conductor.